Master Edge Sensor Adjustment - Ricoh DD 4450 Service Manual

4.7.8 MASTER EDGE SENSOR ADJUSTMENT

Ensures that the sensor detects the leading edge of the master.
Standard: 2.0 volts (within "+0.1" and "-0.1"volts)
Tools: Circuit tester
Rear cover ( p.4-10 "Rear Cover")

1. Connect the terminals of a circuit tester to TP103 and a grounded place (e.g. iron base)
2. Connect the power plug, and turn on the main switch to access SP mode.
3. Select SP6-51 (Master edge sensor voltage).
4. Remove the lower master tray.
5. Pull out the master-making unit from the machine and open the master set cover.
6. Insert the leading edge of the master under the master tension roller, then close the master
set cover and reinstall the master-making unit in the machine.
7. Measure the voltage with the circuit tester, and turn VR103 until the value becomes between
"-0.1" and "+0.1" volts from the standard value (3.0 volts).
When the voltage cannot be adjusted to the standard value, adjust the threshold level of

the master edge sensor. (SP6-51: Master edge sensor voltage)
Standard Value
Master present
3.0V+-0.1V
SM
Threshold level (SP6-51)
2.8V
4-45
Master Feed
Standard Value
Master not present
Above 3.0V
C279